Territory



(No Modl.)

J. THIERRY. PISTON Patented My. 18, 1890.

.dia/ 2,

UNITED STATES PATENT OFFICE.

JAMES THIERRY, OF LARAMIE CITY, W YOMING TERRITORY.

PISTON.

SPECIFICATION forming part of Letters Patent No. 423,499, dated March 18, 1890.

Application filed 0otoher-19,188 9. Serial No. 327.534. (No model.) l

To aZZ whom it may concern:

Be it known that I, JAMES THIERRY, a citizen of the United States, residing at Laramie City, in the county of Albany andTerritory of Wyoning, have invented a new and useful Improvement in Pistons, of which the following is a specification.

My invention relates to improvements in that class of steam-engines in which the cylinder is horizontal;` and the objects of my improvement are, first, to reduce the friction of the piston, and, second, to provide for the self-poising of the same. I attain these objects by the mechanism illustrated in the accompanying drawings, in Which- Figure 1 is a vertical section on the line J K, Fig. 3; Fig. 2, a vertical section on the line L M, Fig. 1; Fig. 3, a horizontal section on the line R S, Fig. 1; Fig. 4, a vertical section on line N O, Fig. 3; and Fig. 5, a vertical section on line P Q, Fig. 3.

Similar letters refer to similar parts th ro ughout the several views.

A is the piston; B, the cylinder; C, the piston-rod, and D D'D" D' the piston-packing rngs.

E E' are 'balance-chambers applied at the top of said piston, provided with steam-passages F F' and limited by said packing-rings and the packing-strips G G' G", supported on springs H H' H' o I is an annular recess permanently filled With live stean during operation, except alternately at the space occupied by either of said chambers during the alternate exhaust and thus reduce the friction and equalize the wear and tear of said'piston and cylinder, so that the former Will not appreciably wear out of center with the latter.

I am aware that prior to my invention horizontal pistons have been carried or floated by steam. Therefore I do notclaim such a combination, broadly; but

What I claim as my invention, and desire to secure by LettersPatent, is-

1. In horizontal stearn-engines, the combination of the piston with packing-strips G G' G", springs H H'` H' and steam-passages F F', substantially as shown, for the purpose set forth.

2. In horizontal steam-engines, the combination of the piston with the recess I, packing-strips G G' G", springs H H' I-I", and stean passages F. F', all substantially as specified.

JAMES THIERRY.

Witnesses:

W. J. HILLS, JAS. M. FENWICK. 

